$http post with angular gives error: possibly unhandled rejection

I've just managed to get my $http post working over Angular. It does what it needs to do, but when I post the data and then refresh the page it gives this error in my console:

Possibly unhandled rejection: {"data":null,"status":-1,"config":{"method":"POST","transformRequest":[null],"transformResponse":[null],"jsonpCallbackParam":"callback","url":"/insert","data":

This is my Angular post call:

app.controller('ContactCtrl', function($scope, $http){
  $scope.formModel = {};
  $scope.onSubmit = function(){
  $http.post('/insert', $scope.formModel)
  console.log('success');
  };
});

And this is my server call in Express.js to my MongoDB:

router.post('/insert', function(req, res, next){
  var item = {
    name: req.body.name,
    adress: req.body.adress,
    postal: req.body.postal,
    city: req.body.city,
    email: req.body.email,
    phone: req.body.phone,
    quotation: req.body.quotation,
    message: req.body.message
};

var data = new UserData(item);
data.save();
console.log('Item inserted');

});

via Larsmanson